1. Field of the Invention
The present invention relates to a semiconductor device using a bipolar transistor.
2. Description of the Related Art
Conventionally, a bipolar transistor has been employed as a current amplifying element which receives a base current as an input and outputs a collector current. For example, when positive collector-emitter voltage V.sub.CE and base-emitter voltage V.sub.BE (V.sub.CE &gt;V.sub.BE) are applied to an npn bipolar transistor, collector current I.sub.C takes amplified positive values with respect to various values of base-emitter voltage V.sub.BE, and in this case, base current I.sub.B is also positive.
Since the conventional bipolar transistor can only perform a predetermined operation, this transistor has a limited application range.